An improved algorithm for reliability bounds of multistate networks

Abstract

Indirect approaches based on minimal path vectors (d-MPs) and/or minimal cut vectors (d-MCs) are reported to be efficient for the reliability evaluation of multistate networks. Given the need to find more efficient evaluation methods for exact reliability, such techniques may still be cumbersome when the size of the network and the states of component are relatively large. Alternatively, computing reliability bounds can provide approximated reliability with less computational effort. Based on Bai’s exact and indirect reliability evaluation algorithm, an improved algorithm is proposed in this study, which provides sequences of upper and lower reliability bounds of multistate networks. Novel heuristic rules with a pre-specified value to filter less important sets of unspecified states are then developed and incorporated into the algorithm. Computational experiments comparing the proposed methods with an existing direct bounding algorithm show that the new algorithms can provide tight reliability bounds with less computational effort, especially for the proposed algorithm with heuristic L1.     

Expected utility, μ-σ preferences,and linear distribution classes: A further result

This article is an extension of Meyer and Sinn's results on the representation of arbitrary von Neumann-Morgenstern functions in - space when the probability distributions to be compared belong to a linear distribution class. It shows that, when absolute risk aversion decreases, stays constant, or increases not too fast, an increase in , given , increases the indifference curve slope: increased riskiness increases the required marginal compensation for risk when risk is measured by the standard deviation of wealth or income.I gratefully acknowledge useful comments by Wolfgang Buchholz, Kai Konrad, Jack Meyer, Hans Schneeweiß, Dominique Thon, and Bengt Arne Wickström.     

Socioeconomic Correlates of Current and Regular Smoking Among College Students in Rhode Island

Objective: The objective of this study was to determine how sociodemographic variables, in particular socioeconomic status, correlate with current and regular smoking among college students in Rhode Island. Participants and Methods: Over a 4-year period (academic year 2000-2001 to 2003-2004), the authors examined sociodemographic correlates of cigarette use among 3,984 students aged 17 to 24 years from 10 colleges and universities in Rhode Island. Results: One-third of participants (32.0%) had smoked a cigarette in the 30 days preceding the questionnaire. Findings from a pair of logistic regression models indicated that participants from upper-income families were more likely to be current smokers—although not regular smokers—suggesting that the effect of socioeconomic status on smoking is partly dependent on the level of addiction. In addition, freshmen were more likely to be current and regular smokers than were upperclassmen, and white students were most likely to be regular smokers. Conclusions: The frequency of college students who reported that they first tried smoking and first smoked regularly while in college increased from freshman to senior year, indicating that the college years are a vulnerable period for smoking initiation and habituation.     

A moral vision: human dignity in the eyes of the founders of sociology

The case argued in this paper is not that the concerns of the founders of sociology are uniformly and in every particular still our own (Runciman, 2008), but that the concepts and methods used to address just one of their concerns were both ground breaking and of enduring value (Shilling and Mellor, 2001, 2011, for example, make a similar claim). Such a concern focused on the kind of morality grounded in a capitalist social order and, by implication, how it might be theorized. This generated in the process the uniquely sociological operationalization of what had seemed hitherto a philosophical concept: human dignity, along with the freedom and autonomy that attend it. Certainly, the priorities differed in each of the contributions to this endeavour but, in coming at the problem from different standpoints, the concept of dignity came to appear more rounded, more substantive and more relevant to the human condition in all its historical specificity. Quite crucially, there is also in these sources from the classical period of sociology an intimation of method: both the way in which human dignity is to be ‘perceived’ within an inter‐personal dialectic at a micro‐level and, at a macro‐level, how we can discern that dignity transcends artificial confinement by any one aspect of life (be it economic, political or cultural).¹     

The Museum of Amor:

No abstract available for this article.     

大地伦理“休谟问题”之辩

大地伦理学在生态学规律基础上提出将对共同体的和谐、稳定和美丽作为生态伦理规则的致思之路被认为遭遇“休谟问题”困境。凯利考特等人从休谟的道德情感基础论的角度出发，通过说明大地伦理学的道德基础是情感，生态学规律的改变是道德情感作用对象的认识而非道德情感本身对大地伦理辩护。超越困境与否争论的途径是消解休谟问题和伦理科学主义思路，有着重视伦理的实践意义。     

Current Situation and Prospects for the Urbanization of Chinese Migrant Workers

本论文运用年龄结构—生命周期方法分析农民工就业状况对他们城镇化的影响。基于中国企业用工年轻化、农民工失业中年化的现状，论文首先运用年龄结构—生命周期模型进行了估算，指出为了全家城镇化，农民工夫妻婚后一般需要连续工作30年。在此基础上，论文构建了农民工工作寿命表，用以估算中国具备城镇化最低限度经济能力的农民工总量。考虑到未来企业用工年龄结构的变化，预计2006年时年龄在30岁以下的6900多万农民工及其家属都已具备在城镇定居的最起码的经济条件。

关键词: 农民工城镇化?农民工就业?年龄结构—生命周期模型?工作年限?中年失业

This article uses the age‐structure/life‐cycle method to analyze the impact of migrant workers’ employment on their urbanization. Since enterprises tend to employ younger workers and unemployed migrant workers tend to be middle‐aged, we first apply the age structure/life cycle model to carry out our estimations, pointing out that in order to complete the urbanization of their families, migrant worker couples usually have to work for thirty years consecutively after marriage. On this basis, the article constructs a working life table for migrant workers and uses it to estimate the total quantity of Chinese migrant workers who have the minimum economic capacity required for urbanization. Taking into consideration future changes in the age structure of enterprise employment, we estimate that over the sixty‐ nine million migrant workers who were under thirty years old in 2006, together with their families, would already be in possession of the minimum economic conditions for settling in urban areas.     

The Interaction between Negative Emotionality and Effortful Control in Early Social‐emotional Development

Interactions between reactive and regulatory dimensions of temperament may be particularly relevant to children's adjustment but are examined infrequently. This study investigated these interactions by examining effortful control as a moderator of the relations of fear and frustration reactivity to children's social competence, internalizing, and externalizing problems. Participants included 306 three‐year‐old children and their mothers. Children's effortful control was measured using observational measures, and reactivity was assessed with both observational and mother‐reported measures. Mothers reported on children's adjustment. Significant interactions indicated that children with higher mother‐reported fear or higher observed frustration and lower executive control showed higher externalizing problems whereas children with higher observed fear and higher delay ability demonstrated lower externalizing problems. These results highlight effortful control as a moderator of the relation between reactivity and adjustment, and may inform the development of interventions geared toward the management of specific negative affects.     

Electronic Technology for Social Work Education and Practice: The Application of Telephone Technology to Counseling

SUMMARY

The author in this article argues for the legitimization of the telephone in one-on-one and group professional practice in social work. She contrasts telephone hotline work and face-to-face counseling with her view of telephone counseling.